The present invention relates to improvements in reconditioning apparatus for bagged material.
Apparatus for breaking up hardened granular or powdered substances contained in a bag, without having first to remove the contents, are known. One such device has been constructed and used to break up sugar, which has hardened over time due to temperature and humidity, contained in commercial quantity 100 lb. paper bags. The bags are fed one-by-one through the machine between a pair of opposed breaker plates and a pair of side crusher plates, arranged generally at right angles to define a rectangular receiving space for the bags and which impart cyclical crushing forces to the bag to break up the hardened material.
In the aforementioned device, the front breaker plate is pivoted on the frame along its lower edge, and the back breaker plate is pivoted on the frame along its upper edge. A motor-driven eccentric drives the free ends of the breaker plates simultaneously back and forth toward and away from each other. At the same time, the eccentric moves the side crusher plates, which are welded onto arms attached to the eccentric, in a circular path toward and away from each other.
In operation, one end of a 100 lb. bag of sugar is inserted between the breaker plates and side crusher plates. The circular motion of the side crusher plates and the back and forth motion of the front and back breaker plates are phased such that the side plates move toward each other at the time that the front and back breaker plates move away from each other. Each time the side plates move together and capture the bag, the breaker plates move apart and release the bag, and the circular motion of the side plates move the bag through the machine (in incremental steps). As the bag moves through the apparatus, the breaker and crusher plates apply a crushing force, alternatively from the sides and from the front and back, to the portion of the bag between the plates, such that by the time the entire bag has moved through the apparatus, the hardened contents have been returned to a powdered or granulated form.
The device is disclosed generally in Fox U.S. Pat. No. 2,689,093, but differs from the described device inasmuch as the side plates, or crusher plates, have an inwardly extending convex surface which is forced into the sides of the 100 lb. bags to help break up the material. Also the pivoting end of the back breaker plate is attached to the frame by a pair of longitudinally extending threaded rods, which are received in cooperating holes fixed relative to the frame, rather than by a hydraulic piston and cylinder unit as shown in the Fox patent drawings.
In order to effect comminution of the sugar in the 100 lb. bags, the plates need to apply a substantial force to the bag sides, front and back, and the apparatus must be capable of applying such forces and withstanding the resultant stresses, which are aggravated by the fact the forces are applied cyclically, machine fatigue thus becoming a factor.
Since large forces are applied to the bags, however, breakage is a significant problem, and is reduced only by precise positioning of the breaker and crusher plates. To help reduce breakage, the spacing between the front and back breaker plates is somewhat adjustable. The pivot rod on the back breaker plate is connected at each end to a block, the blocks in turn being connected to a cross-supporting member arranged between upper and lower plates. The threaded rods used to couple the plate to the frame, are in turn welded to the cross-support. The plates have track supports at each end onto which the block are welded.
A cross member of the frame receives the threaded rods to secure the pivot support on the upper edge of the back breaker plate. The cross member has a pair of large holes, in which a support plate is positioned. Thereafter, the support plate is attached to the cross member, and engages the upper and lower plates to add support. The support plate has a pair of holes arranged to receive the threaded rods. A pair of nuts on each rod, positioned on each side of the hole, are used to adjust the positions of the rods, the cross-supporting member, and thereby the back breaker plate relative to the frame. This arrangement, however, permits only very limited longitudinal adjustability, since the upper and lower plates are constrained by the support plate. Moreover, under the cyclical stresses of machine operation, the blocks tend to loosen and disengage from the track.
The side arms, attached at one end to the side crusher plates, are adjustably attached at their other ends to the eccentric. The free end of each arm is bifurcated, and has a serrated lower surface which engages cooperating serrations on the eccentric. Each arm is attached to the eccentric by a nut and bolt arrangement. The bolt, attached to the eccentric, extends vertically between the tangs of the arm. With the nut loosened, the arm can be adjusted longitudinally to engage a different set of serrations. Once positioned, the nut tightens down over the tangs to secure the arm on the eccentric housing. In practice, however, it has been found that the retaining force exerted by the nuts and the constant machine vibration tend to separate the tangs, causing them to loosen or crack.
Although the supporting arms which carry the side crusher plates can be adjusted lengthwise on the eccentric, no adjustment of the spacing between the crusher plates, and thereby the widthwise adjustment of the bag receiving space, is possible. Commonly, however, granulated materials are packaged for retail in small paper bags, for example 5 lb. sugar bags, which are sold commercially in larger units, for example, in the case of sugar, twelve 5 lb. sugar bags arranged within a 60 lb. paper bundle. It was thought that a Fox type comminuting machine could not be used with respect to such types of double packaged materials. The cross-sectional dimensions of the bundles, dictated by the size and internal arrangement of the 5 lb. bags, tend to vary drastically from the single 100 lb. package commercial counterpart. Also, the inner 5 lb. bags provide internal cross support to the hardened sugar, and thus 12 discreet masses of material need to be crushed without breaking either the interior bags or the outer paper bundle. Moreover, the 60 lb. bundles contain two interior 5 lb. bags, surrounded on three sides by other 5 lb. bags, which, if fed through a Fox type machine, would experience no direct crushing blows from the side crusher plates.
Both for the reasons of non-adjustability and because, as described above, the sugar is double packaged (5 lb. bags within 60 lb. bundles), the Fox type machine was not considered adaptable to 60 lb. bundles of hardened sugar, and sugar packaged in such bundles has continued to be reconditioned by prior art methods of applying blows to the bundles by hand or removing the sugar from the 5 lb. bags, comminuting, and then repackaging, the loose sugar. Both methods are costly and wasteful, however, due to the high percentage of breakage loss in the former, and the expense of removing and repackaging in the latter.